Substrate processing apparatus

ABSTRACT

A substrate processing apparatus has a cup part for receiving processing liquid such as pure water which is splashed from a substrate. The cup part is formed of electrical insulation material. Hydrophilic treatment may be performed on an outer annular surface of the cup part. Water is held on at least one surface of the cup part while processing the substrate. The water may be substantially grounded. With the disclosed apparatus, charged potential of the cup part generated by splashing of pure water can be suppressed, without greatly increasing the manufacturing cost of the substrate processing apparatus. As a result, it is possible to prevent electric discharge from occurring on the substrate due to induction charging of the substrate, in application of the processing liquid onto the substrate.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is a divisional application of U.S. patentapplication Ser. No. 14/340,218, filed Jul. 24, 2014, which is acontinuation of U.S. patent application Ser. No. 11/853,231, filed Sep.11, 2007, now U.S. Pat. No. 8,815,048, issued Aug. 26, 2014, whichclaims the benefit of Japanese Patent Application No. 2006-251637, filedSep. 15, 2006, Japanese Patent Application No. 2006-327938, filed Dec.5, 2006, and Japanese Patent Application No. 2006-328648, filed Dec. 5,2006, which are incorporated herein by reference.

BACKGROUND OF THE INVENTION 1. Field of the Invention

The present invention relates to a technique for processing a substrateby applying processing liquid onto the substrate.

2. Description of the Background Art

In a manufacturing process of a semiconductor substrate (hereinafter,simply referred to as “substrate”), various processings have beenconventionally performed on the substrate, on which an insulating filmsuch as an oxide film is formed, with using a substrate processingapparatus. For example, a processing of etching or the like is performedon a surface of the substrate by applying processing liquid onto thesubstrate while rotating the substrate around the central axisperpendicular to its main surface. Processing liquid splashed from therotating substrate is received by a cup part (splash guard) surroundingthe substrate, thereby preventing the processing liquid from beingsplashed outside the apparatus. Such a cup part is normally formed ofelectrical insulation material such as fluorine resin or vinyl chlorideresin, from the viewpoint of corrosion resistance against the processingliquid.

Japanese Patent Application Laid-Open No. 11-283914 (Document 1)discloses a method of preventing a cup part from being charged inprocessing of a substrate by forming the cup part with antistaticplastic material in a substrate processing apparatus. Japanese PatentApplication Laid-Open No. 2004-356299 and Japanese Patent ApplicationLaid-Open No. 2006-147672 disclose substrate processing apparatuseswhere hydrophilic treatment is performed on an inner annular surface ofa cup part or an outer annular surface of an inner cup part in a casewhere a plurality of cup parts are provided concentrically. In thesubstrate processing apparatuses, suppressed is re-adherence ofprocessing liquid, which is splashed from a substrate, to the substrateby rebounding from the cup part or the like.

In the meantime, a process using pure water as the processing liquid(cleaning process, for example) is performed in the substrate processingapparatus. In this process, frictional charging in a cup part withinsulating properties is caused by pure water with high resistivity(specific resistance) which is splashed from a substrate, and then themain body of the substrate is charged by induction due to electric fieldgenerated by the cup part. When processing liquid with conductivity isapplied onto the substrate in the above state, insulating properties ofan insulating film is broken and electric discharge occurs between theprocessing liquid applied onto the substrate and the main body of thesubstrate with interposing the insulating film. Though it is thought toform the whole cup part with antistatic plastic material as disclosed inDocument 1, such special material is expensive to greatly increase themanufacturing cost of the substrate processing apparatus.

SUMMARY OF THE INVENTION

The present invention is intended for a substrate processing apparatusfor processing a substrate by applying processing liquid onto thesubstrate. It is an object of the present invention to prevent electricdischarge from occurring on the substrate due to induction charging ofthe substrate which is caused by charging of a cup part generated insplashing of pure water, without greatly increasing the manufacturingcost of the substrate processing apparatus.

The substrate processing apparatus in accordance with the presentinvention comprises a holding part for holding a substrate; a processingliquid applying part for applying pure water, which is one type ofprocessing liquid, onto the substrate; and a cup part whose main body isformed of electrical insulation material or semiconductor material, thecup part having an annular sidewall surrounding the holding part toreceive processing liquid splashed from the substrate, the annularsidewall having an internal portion with a resistivity which is smallerthan that of the electrical insulation material forming the main body.

According to the present invention, it is possible to suppress chargedpotential of the cup part generated in splashing of pure water, withoutgreatly increasing the manufacturing cost of the substrate processingapparatus, thereby preventing electric discharge from occurring on thesubstrate due to induction charging of the substrate.

Another preferred substrate processing apparatus comprises a holdingpart for holding a substrate; a processing liquid applying part forapplying pure water, which is one type of processing liquid, onto thesubstrate; and a cup part whose main body is formed of electricalinsulation material or semiconductor material, the cup part surroundingthe holding part to receive processing liquid splashed from thesubstrate, at least one surface of an inner annular surface and an outerannular surface of the cup part including a surface of a member with aresistivity which is smaller than that of the main body. It is therebypossible to prevent electric discharge from occurring on the substratedue to induction charging of the substrate.

Still another preferred substrate processing apparatus comprises aholding part for holding a substrate; a processing liquid applying partfor applying pure water, which is one type of processing liquid, ontothe substrate; a cup part which is formed of electrical insulationmaterial and surrounds the holding part to receive processing liquidsplashed from the substrate, liquid including water being held on atleast one surface of an inner annular surface and an outer annularsurface of the cup part; and a ground part for substantiallyelectrically grounding the liquid held on at least one surface. In sucha substrate processing apparatus, it is possible to further suppress thecharged potential of the cup part.

A substrate processing apparatus according to an aspect of the presentinvention comprises a holding part for holding a substrate; a processingliquid applying part for applying pure water, which is one type ofprocessing liquid, onto the substrate; and at least one cup part each ofwhich is formed of electrical insulation material and surrounds theholding part to receive processing liquid splashed from the substrate,and in the apparatus, liquid including water is held on an outer annularsurface of an outermost cup part out of at least one cup part. It isthereby possible to suppress the charged potential of the cup partwithout affecting a process.

A substrate processing apparatus according to another aspect of thepresent invention comprises a holding part for holding a substrate; aprocessing liquid applying part for applying pure water, which is onetype of processing liquid, onto the substrate; at least one cup parteach of which is formed of electrical insulation material orsemiconductor material and surrounds the holding part to receiveprocessing liquid splashed from the substrate; and a cylindrical memberwhich is provided close to an outer annular surface of an outermost cuppart out of at least one cup part, the cylindrical member having aresistivity which is smaller than that of the outermost cup part. It istherefore possible to suppress the charged potential of the cup partgenerated in splashing of pure water, with using the cylindrical member.

A substrate processing apparatus according to still another aspect ofthe present invention comprises a holding part for holding a substrate;a processing liquid applying part for applying pure water, which is onetype of processing liquid, onto the substrate; and a cup part whose mainbody is formed of electrical insulation material, the cup part having anannular sidewall surrounding the holding part to receive processingliquid splashed from the substrate, an auxiliary dielectric materialwith a dielectric constant, which is higher than that of the electricalinsulation material, being provided as an internal portion of theannular sidewall or being provided on a surface of the annular sidewall.In the substrate processing apparatus, it is possible to suppress thecharged potential of the cup part generated in splashing of pure water,with using the auxiliary dielectric material. As a result, it is therebypossible to prevent electric discharge from occurring on the substratedue to induction charging of the substrate.

The present invention is also intended for a substrate processing methodof processing a substrate by applying processing liquid onto thesubstrate.

These and other objects, features, aspects and advantages of the presentinvention will become more apparent from the following detaileddescription of the present invention when taken in conjunction with theaccompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a view showing a construction of a substrate processingapparatus in accordance with a first preferred embodiment;

FIG. 2 is a flowchart showing an operation flow of the substrateprocessing apparatus for processing a substrate;

FIG. 3 is a view for explaining an operation for applying pure water toan outer annular surface of a cup part;

FIG. 4 is a view showing another example of the substrate processingapparatus;

FIGS. 5 to 7 are views each showing still another example of thesubstrate processing apparatus;

FIG. 8 is a cross-sectional view of a cup part;

FIG. 9 is a view showing still another example of the substrateprocessing apparatus;

FIG. 10 is a cross-sectional view of a cup part;

FIG. 11 is a view showing another example of a cup part;

FIG. 12 is a view showing still another example of the substrateprocessing apparatus;

FIG. 13 is a view showing a construction of a substrate processingapparatus in accordance with a second preferred embodiment;

FIG. 14 is a flowchart showing a part of an operation flow of thesubstrate processing apparatus for processing a substrate;

FIGS. 15 to 17 are views each for explaining a basic operation of thesubstrate processing apparatus;

FIG. 18 is a view showing another example of the substrate processingapparatus;

FIG. 19 is a view showing still another example of the substrateprocessing apparatus;

FIG. 20 is a view showing a construction of a substrate processingapparatus in accordance with a third preferred embodiment;

FIG. 21 is a view showing another example of the substrate processingapparatus;

FIGS. 22 to 24 are views each showing still another example of thesubstrate processing apparatus;

FIG. 25 is a view showing a construction of a substrate processingapparatus in accordance with a fourth preferred embodiment;

FIG. 26 is a cross-sectional view of a cup part;

FIG. 27 is a flowchart showing an operation flow for processing asubstrate by applying processing liquid onto the substrate;

FIG. 28 is a view showing another example of a cup part;

FIG. 29 is a view showing another example of the substrate processingapparatus;

FIG. 30 is a cross-sectional view of a cup part; and

FIG. 31 is a view showing a part of a construction of a substrateprocessing apparatus having a plurality of cup parts.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

FIG. 1 is a view showing a construction of a substrate processingapparatus 1 in accordance with the first preferred embodiment of thepresent invention. The substrate processing apparatus 1 is an apparatusfor performing processings such as etching which is performed byapplying processing liquid onto a semiconductor substrate 9 (forexample, a silicon substrate, and hereinafter simply referred to as“substrate 9”) on which an insulating film (e.g., an oxide film) isformed.

As shown in FIG. 1, the substrate processing apparatus 1 has a substrateholding part 2 for holding the substrate 9 in contact with a lower mainsurface of the substrate 9, a processing liquid applying part 3 which ispositioned above the substrate 9 to eject cleaning liquid onto an uppermain surface of the substrate 9 (hereinafter, referred to as “uppersurface”), a cup part 41 surrounding the substrate holding part 2, anelevating mechanism 5 which is a cylinder mechanism for moving the cuppart 41 in the up and down direction (the vertical direction) in FIG. 1,and a control part 10 for controlling these constituent elements. InFIG. 1, a part of the substrate holding part 2 is showncross-sectionally for convenience of illustration (same as in FIGS. 3 to7, 9, 12, 13, and 15 to 24).

The substrate holding part 2 has a chuck 21 for holding theapproximately disk-shaped substrate 9 in contact with the lower mainsurface and the periphery of the substrate 9 and a rotation mechanism 22for rotating the substrate 9 together with the chuck 21. The rotationmechanism 22 includes a shaft 221 coupled to the lower surface of thechuck 21 and a motor 222 for rotating the shaft 221. By driving themotor 222, the substrate 9 rotates together with the shaft 221 and thechuck 21 around the central axis J1 which is parallel to a normaldirection of the substrate 9 (i.e., the vertical direction to the mainsurface of the substrate 9) with passing through the center of thesubstrate 9.

The processing liquid applying part 3 has an ejection part 32 connectedto a supply pipe 31. The supply pipe 31 is branched off into two pipeson a side which is opposite to the ejection part 32. One pipe isconnected to a supply source of pure water with interposing a pure watervalve 331 and the other is connected to a supply source of predetermined(chemical) solution with interposing the solution valve 332. In theprocessing liquid applying part 3, pure water or (diluted) solution,which is one type of processing liquid, is applied onto the substrate 9from the ejection part 32 by opening the pure water valve 331 or thesolution valve 332. The solution ejected from the ejection part 32 isliquid containing water and has conductivity.

The cup part 41 has an annular sidewall 411 which is arranged around thechuck 21 to prevent the processing liquid applied onto the substrate 9from being splashed around the annular side wall 411, and an upperportion of the annular sidewall 411 is an inclined part 412 whosediameter decreases toward the processing liquid applying part 3 (i.e.,upwards). In the preferred embodiment, the annular sidewall 411 isformed of fluorine resin such as Teflon™ or vinyl chloride resin, aninner annular surface 411 a of the annular sidewall 411 has waterrepellency (hydrophobicity), and an outer annular surface 411 b of theannular sidewall 411 has hydrophilicity by hydrophilic treatment such asa plasma treatment or an ozone treatment. Hydrophilicity (wettability)of the outer annular surface 411 b may be enhanced by increasing itsroughness, depending on material of the cup part 41.

A ring-shaped bottom part 413, which protrudes toward of the centralaxis J1 and covers the lower space of the chuck 21, is attached to alower end portion of the annular sidewall 411, and a drain outlet (notshown) for draining the cleaning liquid is provided in the bottom part413. An auxiliary drain part 414, which spreads on a side opposite tothe side of the bottom part 413 in a ring shape, is formed on the lowerend portion of the annular sidewall 411 and a top end of the auxiliarydrain part 414 bends upwards. As discussed later, water applied to theouter annular surface 411 b of the annular sidewall 411 is drainedthrough the auxiliary drain part 414. The auxiliary drain part 414 isformed of conductive material and grounded by the ground part 61 at aposition apart from the cup part 41.

Next discussion will be made on an operation flow of the substrateprocessing apparatus 1 for processing a substrate by applying theprocessing liquid onto the substrate with reference to FIG. 2. In thesubstrate processing apparatus 1, a process using a unnecessarysubstrate (so-called dummy substrate) is performed as preparation for anactual process of the substrate 9. First, the cup part 41 is moved downby the elevating mechanism 5 until an upper end portion of the cup part41 is positioned below the chuck 21, the dummy substrate is placed onthe chuck 21 by an external carrying mechanism, and held by thesubstrate holding part 2.

FIG. 3 is a view showing the substrate processing apparatus 1immediately after the dummy substrate 9 a is held by the substrateholding part 2. After holding the dummy substrate 9 a, pure water isapplied onto an upper surface of the dummy substrate 9 a by opening thepure water valve 331 (see FIG. 1) in the processing liquid applying part3 and rotation of the dummy substrate 9 a is started by the substrateholding part 2. In this time, the pure water which is applied from theprocessing liquid applying part 3 and is splashed from the rotatingdummy substrate 9 a adheres on the outer annular surface 411 b of theinclined part 412 in the cup part 41. Since the hydrophilic treatment isperformed on the outer annular surface 411 b as discussed above, thepure water applied to the inclined part 412 spreads along the outerannular surface 411 b and is held on the outer annular surface 411 b, toform a thin water layer (i.e., a water film shown by a thick line 71 inFIG. 3) on the outer annular surface 411 b of the annular sidewall 411(Step S10). As discussed later, there is a case where water or otherliquid is held on the inner annular surface of the cup part andtherefore, Step S10 in FIG. 2 represents the content of a generalizedprocess.

The redundant water splashed from the dummy substrate 9 a reaches theauxiliary drain part 414 along the outer annular surface 411 b to bedrained through the auxiliary drain part 414. Actually, since thesubstrate processing apparatus 1 is surrounded with a dedicated cover,there is no problem about the pure water splashed outside the cup part41 (the same as in substrate processing apparatuses 1, 1 a and 1 b inFIGS. 4, 13 and 20 which are discussed later).

In this time, since carbon dioxide (CO.sub.2) and the like in airdissolve into the water layer 71 on the outer annular surface 411 b, thewater layer 71 has a resistivity which is sufficiently smaller than thatof the annular sidewall 411 formed of electrical insulation material. Inother words, a surface layer becoming conductive is formed on the outerannular surface 411 b in the cup part 41. The water layer 71 iscontinuously formed to the auxiliary drain part 414 and it issubstantially electrically grounded by the ground part 61 withinterposing the auxiliary drain part 414.

After the pure water is applied to the outer annular surface 411 b for apredetermined time period with rotation of the dummy substrate 9 a, thepure water valve 331 in FIG. 1 is closed to stop ejection of pure water,and rotation of the dummy substrate 9 a is stopped. After the dummysubstrate 9 a is taken out by the external carrying mechanism, asubstrate 9 to be processed is placed on the chuck 21 and held by thesubstrate holding part 2 (that is to say, the substrate 9 is loaded)(Step S11). Subsequently, the cup part 41 moves up to put the chuck 21in the cup part 41. Rotation of the substrate 9 is started by thesubstrate holding part 2, pure water is applied onto the upper surfaceof the substrate 9 by opening the pure water valve 331 in the processingliquid applying part 3, and thereby pre-rinse using pure water isperformed on the substrate 9 (Step S12). In this time, the pure waterwhich is applied from the processing liquid applying part 3 and issplashed from the rotated substrate 9 is received by the inner annularsurface 411 a of the cup part 41, to cause frictional charging in theinner annular surface 411 a of the cup part 41. In the substrateprocessing apparatus 1, however, since a charge capacity (electricalcapacitance) of the annular sidewall 411 becomes large by forming thewater layer 71 (see FIG. 3) which is the surface layer becomingconductive, a charged potential (relative to a ground potential) of theinner annular surface 411 a is not greatly increased (i.e., a chargedpotential of the cup part 41 is further suppressed than that in a casewhere the water layer 71 is not formed on the outer annular surface 411b). Therefore, the substrate 9 placed on the chuck 21 is hardly chargedby induction.

Next, the pure water valve 331 is closed in the processing liquidapplying part 3 and the processing liquid applied onto the upper surfaceof the substrate 9 is switched from the pure water to the solution byopening the solution valve 332 (Step S13). Application of the solutiononto the substrate 9 is continued for a predetermined time period toperform a processing using the solution on the substrate 9. Similarly tothe case of application of pure water, the solution which is appliedfrom the processing liquid applying part 3 and is splashed from therotating substrate 9 is received by the inner annular surface 411 a ofthe cup part 41 and drained from the drain outlet in the bottom part413.

After the solution is applied onto the substrate 9 for the predeterminedtime period, the solution valve 332 is closed, and the pure water valve331 is opened. Thus, the processing liquid applied onto the uppersurface of the substrate 9 is switched from the solution to the purewater. Subsequently, the upper end portion of the cup part 41 (an endportion of the inclined part 412) moves below the chuck 21 by theelevating mechanism 5 (see FIG. 3), and therefore post-rinse using purewater is performed on the substrate 9 (Step S14). In this time, the purewater which is applied from the processing liquid applying part 3 and issplashed from the rotating substrate 9 adheres on the outer annularsurface 411 b in the inclined part 412 of the annular sidewall 411. Asdescribed above, since the upper end portion of the cup part 41 ispositioned below the substrate 9 while the pure water is ejected fromthe processing liquid applying part 3 in the post-rinse of the substrate9, the pure water splashed from the substrate 9 is easily andefficiently applied to the outer annular surface 411 b of the cup part41. Therefore, even if the water layer 71 on the outer annular surface411 b of the cup part 41 is dried to partly disappear, since the purewater is resupplied on the outer annular surface 411 b, the water layer71 can be repaired.

After completion of the post-rinse for the substrate 9 using the purewater, ejection of pure water is stopped and rotation of the substrate 9is stopped. After the substrate 9 is taken out by the external carryingmechanism (that is to say, after the substrate 9 is unloaded) (StepS15), the next substrate 9 to be processed is placed on the chuck 21 andheld by the substrate holding part 2 (Steps S16, S11). Then, thepre-rinse of the substrate 9 using the pure water (Step S12), theprocessing of the substrate 9 using the solution (Step S13), and thepost-rinse of the substrate 9 using the pure water (Step S14) areperformed similarly to the above operation. In this time, since the purewater is applied to the outer annular surface 411 b of the cup part 41while the preceding substrate 9 which is processed before the in-processsubstrate 9 is held by the substrate holding part 2, it is possible tosurely suppress the charged potential of the cup part 41. Aftercompletion of the post-rinse for the substrate 9, the substrate 9 isunloaded (Step S115).

After the processes in the above Steps S11 to S15 are repeated for eachof a desired number of substrates 9 (Step S16), operations in thesubstrate processing apparatus 1 are completed.

As discussed above, the cup part 41 which receives the processing liquidsplashed from the substrate 9 by surrounding the substrate holding part2 is formed of electrical insulation material in the substrateprocessing apparatus 1 of single wafer type shown in FIG. 1, and wateris held in the outer annular surface 411 b of the cup part 41 inprocessing of the substrate 9. With this structure, it is possible tosuppress the charged potential of the cup part 41 generated in splashingof the pure water, without greatly increasing the manufacturing cost ofthe substrate processing apparatus 1 by forming the whole cup part withspecial conductive material. As a result, it is possible to preventelectric discharge from occurring on the substrate 9 due to inductioncharging of the substrate 9, in application of the processing liquidonto the substrate 9.

In the cup part 41, water can be easily hold in the outer annularsurface 411 b by only performing the hydrophilic treatment on the outerannular surface 411 b and the surface layer with a resistivity, which issmaller than that of the annular sidewall 411, can be easily formed onthe outer annular surface 411 b without providing an additionalexpensive part. Since the water layer 71 is substantially electricallygrounded in a state where water is held in the cup part 41, it ispossible to further suppress the charged potential of the cup part 41.

FIG. 4 is a view showing another example of the substrate processingapparatus 1 which suppresses the charged potential by forming a waterlayer in the cup part. The cup part 41 of the substrate processingapparatus 1 in FIG. 4 is different from that in FIG. 1 in that thehydrophilic treatment performed on the outer annular surface 411 b ofthe annular sidewall 411 is omitted and a textile material 46 (shown bya thick line in FIG. 4) is attached along the outer annular surface 411b by bonding.

Similarly to the case of the substrate processing apparatus 1 in FIG. 1,pure water splashed from the rotating substrate 9 is applied to theouter annular surface 411 b of the annular sidewall 411 in a state wherethe upper end portion of the cup part 41 is positioned below the chuck21, and the pure water penetrates into the textile material 46 to beeasily held in the outer annular surface 411 b in the substrateprocessing apparatus 1 in FIG. 4. A resistivity of the pure water whichpenetrates into the textile material 46 is decreased because CO.sub.2and the like in air dissolve into the pure water, and a surface layerbecoming conductive is formed on the outer annular surface 411 b of thecup part 41. Water held in the textile material 46 is substantiallyelectrically grounded by the ground part 61. In the substrate processingapparatus 1 of FIG. 4, the charged potential of the cup part 41generated in splashing of the pure water in processing the substrate 9is suppressed by the water layer formed on the outer annular surface 411b. As a result, it is possible to prevent electric discharge fromoccurring on the substrate 9 due to induction charging of the substrate9, in application of the processing liquid onto the substrate 9.

There may be a case where a mesh member formed of fluorine resin, forexample, is provided instead of the textile material 46 in the substrateprocessing apparatus 1 of FIG. 4 and the charged potential of the cuppart 41 generated in splashing of the pure water is suppressed byholding water in the mesh member.

FIG. 5 is a view showing still another example of the substrateprocessing apparatus 1 which suppresses the charged potential by forminga water layer in the cup part. In the cup part 41 of the substrateprocessing apparatus 1 in FIG. 5, the hydrophilic treatment is performedon the inner annular surface 411 a of the annular sidewall 411 insteadof the outer annular surface 411 b. A bottom part 413 a of the cup part41 spreads inside from the lower end portion of the annular sidewall 411in a ring shape and the top end of the bottom part 413 a bends upwards.The bottom part 413 a is formed of conductive material having corrosionresistance against the processing liquid and connected to the groundpart 61. The other constituent elements are the same as those of thesubstrate processing apparatus 1 in FIG. 1 and represented by the samereference signs in the following discussion.

When the substrate 9 is processed in the substrate processing apparatus1 of FIG. 5, in the operation of Step S10 in FIG. 2, pure water isapplied onto the upper surface of the dummy substrate and rotation ofthe dummy substrate is started by the substrate holding part 2 in astate where the chuck 21 holding the dummy substrate is put in the cuppart 41 (i.e., pure water is not applied to the outer annular surface411 b of the cup part 41). With this operation, the pure water, which isapplied from the processing liquid applying part 3 and is splashed fromthe rotating dummy substrate, adheres on the inner annular surface 411 ain the cup part 41, and a water layer 71 becoming conductive is therebyformed on the inner annular surface 411 a. Then, after taking out thedummy substrate, the substrate 9 to be processed is placed on the chuck21 (Step S11), and the pre-rinse of the substrate 9 using the pure water(Step S12), the processing of the substrate 9 using the solution (StepS13) and the post-rinse of the substrate 9 using the pure water (StepS14) are performed. The post-rinse of the substrate 9 using the purewater in Step S14 is performed in a state where the chuck 21 is kept inthe cup part 41.

In the substrate processing apparatus 1 of FIG. 5, since water is heldin the inner annular surface 411 a of the cup part 41, it is suppressedthat frictional charging occurs in the inner annular surface 411 a ofthe cup part 41 by the pure water splashed from the rotating substrate 9in processing of the substrate 9. Even if the frictional chargingoccurs, the charged potential of the cup part 41 is surely suppressed bythe water layer 71 which is substantially grounded through the groundpart 61. As a result, it is possible to prevent electric discharge fromoccurring on the substrate 9 due to induction charging of the substrate9, in application of the processing liquid onto the substrate 9. In thesubstrate processing apparatus 1 of FIG. 5, since a portion formed ofconductive material is only a part (the bottom part 413 a) of the cuppart 41, the manufacturing cost of the cup part 41 is not greatlyincreased. In the substrate processing apparatus 1 of FIG. 5, there maybe a case where a textile material or a mesh member is provided in theinner annular surface 411 a of the cup part 41 and water is held in theinner annular surface 411 a.

Next discussion will be made on other technique of suppressing thecharged potential of the cup part in the substrate processing apparatus1. FIG. 6 is a view showing still another example of the substrateprocessing apparatus 1. In a cup part 41A of the substrate processingapparatus 1 of FIG. 6, a conductive resin film 47 (shown by a thick linein FIG. 6) is attached on an outer annular surface of a main bodyinstead of the textile material 46 in the substrate processing apparatus1 of FIG. 4. With this structure, a whole outer annular surface 411 b ofthe cup part 41A becomes a surface of the conductive resin film 47. Aground part 61 is directly connected to the conductive resin film 47 toelectrically ground it. The conductive resin film 47 may be fixed withscrews or the like other than bonding, and the conductive resin film maybe formed on the outer annular surface of the main body in the cup part41A by coating.

When the substrate 9 is processed in the substrate processing apparatus1, the operation of Step S10 in FIG. 2 is omitted and the chuck 21 iskept in the cup part 41A also in the post-rinse of the substrate 9 usingthe pure water in Step S14 (i.e., the pure water is not applied to theouter annular surface 411 b of the cup part 41A).

As discussed above, it is possible to easily provide a member with aresistivity, which is smaller than that of the main body, in the wholecircumference of the cup part 41A, only by attaching the conductiveresin film 47 on the outer annular surface of the main body in thesubstrate processing apparatus 1 of FIG. 6. Thus, the charge capacity ofthe annular sidewall 411 becomes large, and the charged potential of thecup part 41A generated in splashing of the pure water can be suppressedin the whole circumference of the annular sidewall 411 withoutperforming the operation for applying the pure water onto the outerannular surface 411 b, thereby preventing electric discharge fromoccurring on the substrate 9. Since the conductive resin film 47 iselectrically grounded in the substrate processing apparatus 1 of FIG. 6,it is possible to further suppress the charged potential of the cup part41A.

FIG. 7 is a view showing still another example of the substrateprocessing apparatus 1, and FIG. 8 is a cross-sectional view of a cuppart 41A at the position indicated by the arrows I-I in FIG. 7. As shownin FIGS. 7 and 8, an annular sidewall 411 of the cup part 41A has aplurality of (four in the example of FIG. 8) conductive members 47 awhich are formed of conductive resin, conductive carbon (such as glassycarbon) or the like, and a resistivity of the conductive members 47 a ismade smaller than that of a main body of the cup part 41A formed ofelectrical insulation material (in the cup part 41A of FIG. 7, theresistivity of the conductive members 47 a is made smaller than that ofa portion excluding the conductive members 47 a in the annular sidewall411). The plurality of conductive members 47 a are arranged in acircumferential direction of the cup part 41A at regular intervals (thatis to say, the plurality of conductive members 47 a are arranged along acircle around the central axis J1 at equal angle intervals). Actually,the plurality of conductive members 47 a are fitted into a plurality ofrecessed portions, respectively, which are formed on an outer annularsurface 411 b of the cup part 41A and each extending along the centralaxis J1 and surfaces of the conductive members 47 a, which are oppositeto the other surfaces on the side of the central axis J1, are includedin the outer annular surface 411 b of the annular sidewall 411. Eachconductive member 47 a is grounded by a ground part 61. As describedabove, in the case that the outer annular surface 411 b partly includesthe surfaces of the conductive members 47 a with a resistivity which issmaller than that of the main body of the cup part 41, the chargecapacity of the annular sidewall 411 becomes large, thereby suppressingthe charged potential of the cup part 41A generated in splashing of thepure water.

In the cup parts 41A in FIGS. 6 and 7, since the outer annular surfaces411 b include the surface(s) of the member(s) with a resistivity whichis smaller than that of the main body, the charged potential of the cupparts 41A generated in splashing of the pure water can be suppressed toprevent electric discharge from occurring on the substrate 9 due toinduction charging of the substrate 9. Also, it is possible tomanufacture the cup parts 41A of FIGS. 6 and 7 at low cost in comparisonwith a case where the whole cup part is formed of special conductivematerial.

Next discussion will be made on still another technique of suppressingthe charged potential of the cup part in the substrate processingapparatus 1. FIG. 9 is a view showing still another example of thesubstrate processing apparatus 1, and FIG. 10 is a cross-sectional viewof a cup part 41B at the position indicated by the arrows II-II in FIG.9. As shown in FIGS. 9 and 10, an annular sidewall 411 of the cup part41B has a deep ring-shaped groove 415 around the central axis J1, andthe ring-shaped groove 415 is filled with a liquid 47 b withconductivity, such as water into which CO.sub.2 dissolves or liquidwhere ammonium chloride (NH.sub.4Cl) is dissolved into methanol(CH.sub.3OH). As discussed later, the liquid 47 b is liquid sealed inthe annular sidewall 411 and hereinafter referred to as “sealed liquid47 b”. As shown in FIG. 9, since an opening of the ring-shaped groove415 which is on the side of an inclined part 412 is closed by aring-shaped lid member 416, the sealed liquid 47 b is held (sealed) inthe annular sidewall 411. In the annular sidewall 411, a part of anouter portion of the ring-shaped groove 415 functions as an electrodepart 417 which is formed of conductive material such as conductive resinand the electrode part 417 is connected to a ground part 61, and thusthe sealed liquid 47 b is substantially grounded.

In the cup part 41B shown in FIGS. 9 and 10, the annular sidewall 411,which surrounds the substrate holding part 2 to receive the processingliquid splashed from the substrate 9, has an internal portion with aresistivity which is smaller than that of the material forming a mainbody of the cup part 41B as discussed above, and the internal portionextends continuously in a circumferential direction of the annularsidewall 411 (in the cup part 41B of FIG. 9, the main body is a portionexcluding the sealed liquid 47 b in the annular sidewall 411). With thisstructure, the charge capacity of the annular sidewall 411 becomeslarge, and the charged potential of the cup part 41B generated insplashing of the pure water can be suppressed in the whole circumferenceof the annular sidewall 411, thereby preventing electric discharge fromoccurring on the substrate 9. Since the sealed liquid 47 b iselectrically grounded, it is possible to further suppress the chargedpotential of the cup part 41B. Pure water is normally used in processingthe substrate 9, and therefore, the sealed liquid can be easily preparedin a case where water containing dissolved CO.sub.2 is used as thesealed liquid.

FIG. 11 is a view showing another example of the cup part 41B and is across-sectional view of the cup part 41B corresponding to FIG. 10. Inthe cup part 41B of FIG. 11, a plurality of deep holes 415 a in each ofwhich a cross section perpendicular to the central axis J1 is roundshape (actually, four holes 415 a each of which has an approximatelysame depth as the ring-shaped groove 415 of FIG. 9) are formed, they arearranged in a circumferential direction of the annular sidewall 411 atregular intervals, and a cylindrical conductive member 47 c, beingformed of conductive resin, conductive carbon (for example, glassycarbon) or the like, is inserted into each hole 415 a. Each conductivemember 47 c is connected to a ground part 61 (not-shown) through a smallhole which is formed outside the conductive member 47 c in the annularsidewall 411. As discussed above, in the case that the cup part 41B hasan internal portion which is a set of conductive members 47 c arrangedin the circumferential direction of the annular sidewall 411 as parts ofthe annular sidewall 411 and the internal portion has a resistivitywhich is smaller than that of the material forming the main body of theannular sidewall 411, it is possible to suppress the charged potentialof the cup part 41B due to the splashed pure water.

Thus, in the cup part 41B in FIGS. 10 and 11, since the annular sidewall411 has the internal portion with a resistivity which is smaller thanthat of the material forming the main body of the cup part 41B, thecharged potential of the cup part 41B generated in splashing of the purewater can be suppressed to prevent electric discharge from occurring onthe substrate 9 due to induction charging of the substrate 9. Also, itis possible to manufacture the cup part 41B of FIGS. 10 and 11 at lowcost in comparison with a case where the whole cup part is formed ofspecial conductive material. There may be a case where a ring-shapedconductive member formed of conductive resin, conductive carbon, or thelike is inserted into the ring-shaped groove 415 of FIG. 10 and thesealed liquid is sealed in the holes 415 a of FIG. 11. Portions of theconductive member and portions of the sealed liquid may be formed in theannular sidewall 411 so that their positions in the circumferentialdirection are shifted mutually.

Next, discussion will be made on still another technique of suppressingthe charged potential of the cup part in the substrate processingapparatus 1. FIG. 12 is a view showing still another example of thesubstrate processing apparatus 1. In the substrate processing apparatus1 of FIG. 12, an approximately cylindrical member 81 (Hatching of itscross section is omitted in FIG. 12. The same is applied to acylindrical member 81 a of FIG. 23 discussed later) is provided aroundan annular sidewall 411 of a cup part 41C. The inner surface of thecylindrical member 81 is along an outer annular surface 411 b of theannular sidewall 411 and a small clearance is formed between the innersurface of the cylindrical member 81 and the outer annular surface 411 b(for example, the width of the clearance is 1 millimeter (mm) to 10centimeters (cm)). The cylindrical member 81 is formed of metal such asstainless steel and its surface is coated with fluorine resin, e.g.,Teflon™ or the like. Also, the cylindrical member 81 is grounded by aground part 61.

In the substrate processing apparatus 1 of FIG. 12, since the conductivecylindrical member 81 is provided close to the outer annular surface 411b of the cup part 41C, the charge capacity of the annular sidewall 411becomes large substantially. For this reason, the charged potential ofthe cup part 41C generated in splashing of the pure water can besuppressed without greatly increasing the manufacturing cost of thesubstrate processing apparatus 1 by forming the whole cup part with aspecial conductive material. As a result, it is possible to preventelectric discharge from occurring on the substrate 9 due to inductioncharging of the substrate 9. The charged potential of the cup part 41Ccan be further suppressed by grounding the cylindrical member 81.

In the meantime, it is required to prevent metal impurities fromadhering on the substrate 9, for maintaining a constant yield inmanufacturing of semiconductor products in processing of the substrate 9in the substrate processing apparatus 1. Therefore, in order to avoidelution of metal in a cup part, metal cannot be used in an internalportion of a cup part or a surface of the cup part in general design.Conversely, since the cylindrical member 81 is provided away from thecup part 41C in the substrate processing apparatus 1 of FIG. 12, it ispossible to form the cup part 41C at low cost by using metal. Theabove-discussed cylindrical member 81 is coated with fluorine resin toprevent its corrosion. Naturally, the cylindrical member 81 may beformed of conductive resin or conductive carbon.

FIG. 13 is a view showing a construction of a substrate processingapparatus 1 a in accordance with the second preferred embodiment of thepresent invention. In the substrate processing apparatus 1 a of FIG. 13,a plurality of cup parts 42 to 45 are arranged concentrically and aplurality of kinds of solution can be ejected from a processing liquidapplying part 3 a. An elevating mechanism 5 of the substrate processingapparatus 1 a has a motor 51 and a ball screw mechanism 52, and theelevating mechanism 5 can move the cup parts 42 to 45 relatively to asubstrate holding part 2 in a direction along the central axis J1 as aunit. Constituent elements of the substrate holding part 2 are the sameas those in the substrate processing apparatus 1 of FIG. 1, and acontrol part is not shown in the substrate processing apparatus 1 a ofFIG. 13 (the same as in a substrate processing apparatus 1 b of FIG. 20discussed later).

In respective cup parts 42 to 45, annular sidewalls 421, 431, 441, 451and bottom parts 423, 433, 443, 453 are provided separately and theplurality of bottom parts 423, 433, 443, 453 are formed as a unit. Indetail, the plurality of bottom parts 423, 433, 443, 453 formed ofelectrical insulation material are arranged in a ring shape around thecentral axis J1. A conductive plate 490 which is grounded is provided incontact with lower surfaces of the plurality of bottom parts 423, 433,443, 453 (the lower surfaces are surfaces opposite to the upper surfacesfacing the processing liquid applying part 3 a). Cylindrical partitions491, 492, 493, 494, which protrude toward the processing liquid applyingpart 3 a (i.e., upwards) around the central axis J1, are respectivelyarranged in a border between the bottom parts 423 and 433, a borderbetween the bottom parts 433 and 443, a border between the bottom parts443 and 453, and a border outside of the bottom part 453. A lowerportion of each of the annular sidewalls 421, 431, 441, 451 is dividedinto an inner cylindrical part 4211, 4311, 4411, 4511 and an outercylindrical part 4212, 4312, 4412, 4512 (see reference signs on the leftside of FIG. 13), so that it is provided over the partition 491, 492,493, 494. Upper portions of the annular sidewalls 421, 431, 441, 451 areinclined parts 422, 432, 442, 452 each of which has a diameter whichdecreases toward the processing liquid applying part 3 a. The cup part45 is located outermost, the cup part 44 is located inside the cup part45, the cup part 43 is located inside the cup part 44, and then the cuppart 42 is located inside the cup part 43. A distance between theprocessing liquid applying part 3 a and the inclined part 422, 432 or442 of the cup part 42, 43 or 44 is longer than that between theprocessing liquid applying part 3 a and the inclined part 432, 442 or452 of the cup part 43, 44 or 45 (i.e., the inner the cup part islocated, the longer a distance between the processing liquid applyingpart 3 a and the cup part is).

Each of the annular sidewalls 421, 431, 441, 451 is formed of electricalinsulation material, and the same hydrophilic treatment is performed ontheir inner annular surfaces 421 a, 431 a, 441 a, 451 a and their outerannular surfaces 421 b, 431 b, 441 b, 451 b (see reference signs on theleft side of FIG. 13). In the lower portions of the annular sidewalls421, 431, 441, 451, inner surfaces of the inner cylindrical parts 4211,4311, 4411, 4511 are regarded as parts of the inner annular surfaces 421a, 431 a, 441 a, 451 a, and outer surfaces of the outer cylindricalparts 4212, 4312, 4412, 4512 are regarded as parts of the outer annularsurfaces 421 b, 431 b, 441 b, 451 b in the following description.

The elevating mechanism 5 has a supporting member 53 which is formed ofthe same electrical insulation material as the cup parts 42 to 45, andan end portion of the supporting member 53 is connected to the annularsidewall 451 of the outer cup part 45 (hereinafter, also referred to as“outermost cup part 45”). The annular sidewalls 421, 431, 441, 451 ofthe plurality of cup parts 42 to 45 are partly connected one another. Bydriving the motor 51, the plurality of annular sidewalls 421, 431, 441,451 is moved up and down relatively to the substrate holding part 2 inthe direction along the central axis J1 as a unit with use of thesupporting member 53. The supporting member 53 is provided with aconductive sheet 531 which is grounded through the ball screw mechanism52, and the same hydrophilic treatment as the cup parts 42 to 45 is alsoperformed on a surface of the supporting member 53.

The processing liquid applying part 3 a has four valves 331 to 334. Purewater is ejected from an ejection part 32 by opening a pure water valve331, first solution is ejected from the ejection part 32 by opening afirst solution valve 332, second solution is ejected from the ejectionpart 32 by opening the second solution valve 333, and then thirdsolution is ejected from the ejection part 32 by opening a thirdsolution valve 334. The first to third solution have conductivity andare liquid including water.

FIG. 14 is a flow chart showing a part of an operation flow of thesubstrate processing apparatus 1 a for processing a substrate byapplying processing liquid onto the substrate and shows the operation inStep S13 of FIG. 2. Discussion will be made on a basic operation of thesubstrate processing apparatus 1 a at first, with reference to Steps S11to S16 of FIG. 2 and FIG. 14.

In the basic operation of the substrate processing apparatus 1 a in FIG.13, first, a substrate 9 is placed on a chuck 21 and held by thesubstrate holding part 2 (FIG. 2: Step S11), and the cup parts 42 to 45move upwards by the elevating mechanism 5 and the substrate 9 isdisposed in a position (hereinafter, referred to as “pre-rinseposition”) between the inclined part 422 of the innermost annularsidewall 421 and the inner cylindrical part 4211 as shown in FIG. 15.Rotation of the substrate 9 is started and pure water is applied ontothe substrate 9 from the processing liquid applying part 3 a (see FIG.1), to perform pre-rinse of the substrate 9 using pure water (Step S12).In this time, pure water splashed from the rotating substrate 9 isreceived by the inner annular surface 421 a of the annular sidewall 421in the cup part 42. The redundant pure water is drained from a drainoutlet provided in the bottom part 423.

After a predetermined time period has passed from a starting time ofapplying pure water, ejection of pure water is stopped in the processingliquid applying part 3 a, the cup parts 42 to 45 move downwards, andthen the substrate 9 is disposed in a position between the inclined part432 of the second innermost annular sidewall 431 and the inclined part422 of the innermost annular sidewall 421 as shown in FIG. 16. Rotationof the substrate 9 is kept while the substrate 9 moves up and down butmay be temporally stopped in the substrate processing apparatus 1 a.

Ejection of the first solution is started by the processing liquidapplying part 3 a and processing with the first solution is performed onthe substrate 9 (FIG. 14: Step S131). In this time, most of the firstsolution splashed from the rotating substrate 9 is received by the innerannular surface 431 a of the annular sidewall 431 in the cup part 43,and the first solution dripped from the inner annular surface 431 a anda part of the first solution splashed from the substrate 9 also adhereon the outer annular surface 421 b of the innermost annular sidewall421. The redundant first solution is collected from a collection outletprovided in the bottom part 433 and it is reused (the same as in thesecond and third solutions which are discussed later).

After a predetermined time period has passed from start of ejection ofthe first solution, ejection of the first solution from the processingliquid applying part 3 a is stopped, the cup parts 42 to 45 move upwardsby the elevating mechanism 5, and then the substrate 9 is returned tothe pre-rinse position shown in FIG. 15. Subsequently, application ofpure water onto the substrate 9 is started and the first solutionexisting on the substrate 9 is removed by pure water (Step S132). Afterejection of pure water from the ejection part 32 is continued for apredetermined time period, it is stopped and the elevating mechanism 5moves the substrate 9 up to a position between the inclined part 442 ofthe annular sidewall 441 and the inclined part 432 of the annularsidewall 431. Ejection of the second solution is started and processingwith the second solution is performed on the substrate 9 (Step S133). Inthis time, most of the second solution splashed from the rotatingsubstrate 9 is received by the inner annular surface 441 a of theannular sidewall 441 in the cup part 44 (see FIG. 13). The secondsolution dripped from the inner annular surface 441 a and a part of thesecond solution splashed from the substrate 9 also adhere on the outerannular surface 431 b of the inner annular sidewall 431.

After a predetermined time period has passed from start of ejection ofthe second solution, ejection of the second solution from the processingliquid applying part 3 a is stopped. The substrate 9 is returned to thepre-rinse position and application of pure water onto the substrate 9 isperformed for a predetermined time period, to remove the second solutionexisting on the substrate 9 by pure water (Step S134). Subsequently,application of pure water is stopped and the substrate 9 is disposed ina position between the inclined part 452 of the annular sidewall 451 andthe inclined part 442 of the annular sidewall 441. Ejection of the thirdsolution is started and processing with the third solution is performedon the substrate 9 (Step S135). In this time, most of the third solutionsplashed from the rotating substrate 9 is received by the inner annularsurface 451 a of the annular sidewall 451 in the outermost cup part 45.The third solution dripped from the inner annular surface 451 a and apart of the third solution splashed from the substrate 9 also adhere onthe outer annular surface 441 b of the annular sidewall 441.

After a predetermined time period has passed from start of ejection ofthe third solution, ejection of the third solution from the processingliquid applying part 3 a is stopped, the cup parts 42 to 45 movedownwards and an upper end portion of the annular sidewall 451 ispositioned below the substrate 9 as shown in FIG. 17. Then, pure wateris ejected onto the substrate 9 from the ejection part 32 and thepost-rinse of the substrate 9 is performed with the pure water (FIG. 2:Step S14). In this time, the pure water splashed from the rotatingsubstrate 9 is applied to the outer annular surface 451 b of theinclined part 452 in the annular sidewall 451. After completing thepost-rinse of the substrate 9, the substrate 9 is unloaded (Step S15)and the next substrate 9 to be processed is loaded in the substrateprocessing apparatus 1 a (Steps S16, S11).

As preparation for the actual operation in the substrate processingapparatus 1 a, first, a dummy substrate is loaded, the same operationsas the above Steps S12 to S14 are performed, and liquid including wateris held on the inner annular surfaces and the outer annular surfaces ofthe cup parts 42 to 45 (Step S10). Specifically, in the operationcorresponding to Step S12 (and Steps S132, S134), pure water splashedfrom the rotating dummy substrate is received by the inner annularsurface 421 a of the annular sidewall 421 to form a water layer (shownby a thick line 72 a in FIGS. 15 and 17) on the inner annular surface421 a of the cup part 42. In the operation corresponding to Step S131,the first solution splashed from the rotating dummy substrate isreceived by the inner annular surface 431 a of the annular sidewall 431and also adheres on the outer annular surface 421 b of the annularsidewall 421, to form first solution layers (shown by thick lines 73 a,72 b in FIGS. 16 and 17) on the inner annular surface 431 a of the cuppart 43 and the outer annular surface 421 b of the cup part 42,respectively. Also, in the operation corresponding to Step S133, thesecond solution splashed from the rotating dummy substrate is receivedby the inner annular surface 441 a of the annular sidewall 441 and alsoadheres on the outer annular surface 431 b of the annular sidewall 431,to form second solution layers (shown by thick lines 74 a, 73 b in FIG.17) on the inner annular surface 441 a of the cup part 44 and the outerannular surface 431 b of the cup part 43, respectively. In the operationcorresponding to Step S135, the third solution splashed from therotating dummy substrate is received by the inner annular surface 451 aof the annular sidewall 451 and also adheres on the outer annularsurface 441 b of the annular sidewall 441, to form third solution layers(shown by thick lines 75 a, 74 b in FIG. 17) on the inner annularsurface 451 a of the outermost cup part 45 and the outer annular surface441 b of the cup part 44, respectively. Then, in the operationcorresponding to Step S14, the pure water splashed from the rotatingdummy substrate is received by the outer annular surface 451 b of theannular sidewall 451 and a water layer becoming conductive (shown by athick line 75 b in FIG. 17) is also formed on the outer annular surface451 b of the outermost cup part 45. As a result, each surface of theinner annular surfaces 421 a, 431 a, 441 a, 451 a and the outer annularsurfaces 421 b, 431 b, 441 b, 451 b in the cup parts 42 to 45, has thewater layer 72 a or 75 b, the first solution layer 73 a or 72 b, thesecond solution layer 74 a or 73 b or the third solution layer 75 a or74 b, as a surface layer with a resistivity which is smaller than thatof the annular sidewalls 421, 431, 441, 451.

Actually, when the pure water is applied to the outer annular surface451 b of the outermost cup part 45, the pure water also adheres on asurface of the supporting member 53 in FIG. 13, and thus the water layer75 b of the outer annular surface 451 b is substantially electricallygrounded with interposing a water layer formed on the surface of thesupporting member 53, the conductive sheet 531, and the ball screwmechanism 52. In other words, the water layer on the surface of thesupporting member 53, the conductive sheet 531, and the ball screwmechanism 52 serve as a ground part for grounding the water layer 75 b.The conductive sheet 531 may be directly connected to the water layer 75b of the outer annular surface 451 b.

After unloading the dummy substrate, the above Steps S11 to S16 inaccordance with the basic operation of the substrate processingapparatus 1 a are performed on a substrate 9 to be actually processed.In this time, the surface layer becoming conductive, which is formed onthe inner annular surface 421 a of the inner cup part 42 in FIG. 17,suppresses occurrence of frictional charging in the inner annularsurface 421 a of the cup part 42, which is caused by the pure watersplashed from the rotating substrate 9 in Steps S12, S132, and S134.Induction charging of the substrate 9 is surely suppressed by thesurface layers which are formed on the outer annular surface 421 b ofthe cup part 42 and the inner annular surfaces and the outer annularsurfaces of the cup parts 43 to 45 which are located outside the cuppart 42. Further, the surface layer formed on the outer annular surface451 b of the outermost cup part 45 suppresses occurrence of frictionalcharging in the outer annular surface 451 b of the outermost cup part45, caused by the pure water splashed from the rotating substrate 9 inStep S14, and induction charging of the substrate 9 is surely suppressedby the surface layers which are formed on the outermost cup part 45 andthe cup parts 42 to 44 which are located inside the outermost cup part45. Also, even if the bottom parts 423, 433, 443, 453 of the cup parts42 to 45 in FIG. 13 are charged, charging potential of the bottom parts423, 433, 443, 453 is reduced by the conductive plate 490, therebysuppressing induction charging of the substrate 9.

Also in Steps S12, S131 to S135, and S14 which are performed on thesubstrate 9 to be actually processed, since the pure water, the firstsolution, the second solution or the third solution is applied to eachsurface of the inner annular surfaces 421 a, 431 a, 441 a, 451 a and theouter annular surfaces 421 b, 431 b, 441 b, 451 b of the cup parts 42 to45, each surface of the inner annular surfaces 421 a, 431 a, 441 a, 451a and the outer annular surfaces 421 b, 431 b, 441 b, 451 b of the cupparts 42 to 45 surely keeps a state where the surface holds water withconductivity, the first solution, the second solution, or the thirdsolution in processing the next substrate 9 which is processed after theabove substrate 9.

Herein, discussion will be made on an example of an electric dischargephenomenon which occurs on a substrate in a substrate processingapparatus in accordance with an example for comparison. The substrateprocessing apparatus in accordance with the example for comparison hasthe same construction as the substrate processing apparatus 1 a of FIG.13 and the hydrophilic treatment is not performed on any surfaces ofinner annular surfaces and outer annular surfaces of a plurality of cupparts. In the substrate processing apparatus, pure water is applied ontothe substrate in a state where the substrate is disposed in thepre-rinse position, the pure water is splashed toward the innermost cuppart, and then the cup part is charged after the pure water is drippedfrom the cup part. Then, the main body of the substrate is charged byinduction because of charging of the cup part. In this time, if the purewater is kept on the substrate, CO.sub.2 and the like dissolves into thepure water, the pure water changes to water with conductivity, andconsequently, electric discharge can occur on the substrate. Also, ifthe cup parts move up and down in a state where the water becomingconductive remains on the substrate, a relative position between thesubstrate and the charged cup part is changed to alter the potential ofthe main body of the substrate. As a result, electric discharge canoccur on the substrate (that is to say, dielectric breakdown of aninsulating film on the substrate occurs) while the cup parts move up anddown.

On the other hand, in the substrate processing apparatus 1 a of FIG. 13,since the processing for the substrate 9 is performed in a state wherethe water, the first solution, the second solution, or the thirdsolution is held on each surface of the inner annular surfaces 421 a,431 a, 441 a, 451 a and the outer annular surfaces 421 b, 431 b, 441 b,451 b of the cup parts 42 to 45, the charged potential of a cup partcaused by the splashed pure water can be surely suppressed by liquidlayers including water which are formed on the cup part and other cuppart. As a result, it is possible to prevent occurrence of electricdischarge on the substrate 9 which is caused by charging of the cuppart, in application of the processing solution onto the substrate 9, upand down movement of the cup parts 42 to 45, or the like. Also, theinner cup parts 42 to 44 may be substantially electrically groundeddepending on design of the substrate processing apparatus 1 a (the sameas in substrate processing apparatuses in FIGS. 18 and 19 discussedlater).

FIG. 18 is a view showing another example of the substrate processingapparatus 1 a. Similarly to the cup part 41A of FIG. 6, the conductiveresin film 47 is attached on each surface of inner annular surfaces andouter annular surfaces of main bodies in annular sidewalls 421, 431,441, 451 in the substrate processing apparatus 1 a of FIG. 18. Eachsurface of inner annular surfaces 421 a, 431 a, 441 a, 451 a and outerannular surfaces 421 b, 431 b, 441 b, 451 b of cup parts 42A to 45A isthe surface of the conductive resin film 47 in the substrate processingapparatus 1 a of FIG. 18. Since the outer cylindrical part 4512 of theannular sidewall 451 in the outermost cup part 45 is omitted, the outerannular surface 451 b includes a portion corresponding to the outerannular surface of the inner cylindrical part 4511. The outer annularsurface 451 b of the outermost cup part 45 is directly connected to aground part 61. Arrangement of the plurality of cup parts 42A to 45A andthe other constituent elements of the apparatus are the same as those inthe substrate processing apparatus 1 a of FIG. 13 and are represented bythe same reference signs.

When the substrate 9 is processed in the substrate processing apparatus1 a of FIG. 18, the operation of Step S10 in FIG. 2 is omitted and thechuck 21 is disposed in the cup parts 42A to 45A also in the post-rinseof the substrate 9 using pure water in Step S14 (that is to say, purewater is not applied to the outer annular surface 451 b of the outermostcup part 45A) (the same as in the substrate processing apparatus 1 a ofFIG. 19 and substrate processing apparatuses 1 b of FIGS. 21 to 23 whichare discussed later).

As described above, since the inner annular surfaces 421 a, 431 a, 441a, 451 a and the outer annular surfaces 421 b, 431 b, 441 b, 451 b ofthe respective cup parts 42A to 45A are surfaces of members with aresistivity which is smaller than that of the main bodies of the annularsidewalls 421, 431, 441, 451 in the substrate processing apparatus 1 aof FIG. 18, the charged potential of the cup part which is caused by theplashing pure water can be surely suppressed and consequently, it ispossible to prevent occurrence of electric discharge on the substrate 9caused by charging of the cup part, in application of the processingsolution onto the substrate 9 or the like. Similarly to the cup part 41Aof FIG. 7, the inner annular surfaces and the outer annular surfaces ofthe cup parts 42A to 45A may partly include the surfaces of theconductive members arranged in the circumferential direction at regularintervals.

FIG. 19 is a view showing still another example of the substrateprocessing apparatus 1 a. In cup parts 42B to 45B in the substrateprocessing apparatus 1 a of FIG. 19, a plurality of rod conductivemembers (shown by thick lines 47 c in FIG. 19) are provided in each ofannular sidewalls 421, 431, 441, 451, similarly to the cup part 41B ofFIG. 11. Actually, the plurality of conductive members 47 c are arrangedin the circumferential direction of the annular sidewalls 421, 431, 441,451 at regular intervals (see FIG. 11). Inner annular surfaces 421 a,431 a, 441 a, 451 a and outer annular surfaces 421 b, 431 b, 441 b, 451b of the cup parts 42B to 45B are surfaces of electrical insulationmaterial and they have water repellency (the same as in the substrateprocessing apparatuses 1 b of FIGS. 22 and 23 which are discussedlater). Arrangement of the plurality of cup parts 42B to 45B and theother constituent elements of the apparatus are the same as those in thesubstrate processing apparatus 1 a of FIG. 13 and are represented by thesame reference signs.

In the respective cup parts 42B to 45B all of which have the samestructure, the annular sidewalls 421, 431, 441, 451 have internalportions with a resistivity which is smaller than that of the materialforming their main bodies (in the cup parts 42B to 45B of FIG. 19, themain bodies are portions excluding the conductive members 47 c in theannular sidewalls 421, 431, 441, 451) in the substrate processingapparatus 1 a of FIG. 19. With this structure, charged potential of acup part caused by the splashed pure water can be surely suppressed toprevent occurrence of electric discharge on the substrate 9. Theconductive member or the sealed liquid may be provided in the internalportions of the annular sidewalls 421, 431, 441, 451 across their wholecircumferences (the same as in an annular sidewall 451 of FIG. 22discussed later).

FIG. 20 is a view showing the substrate processing apparatus 1 b havinga plurality of cup parts 42 to 45 in accordance with the third preferredembodiment of the present invention. The outer cylindrical part 4512 ofthe annular sidewall 451 in the outer cup part 45 (i.e., the outermostcup part 45) in the substrate processing apparatus 1 a of FIG. 13 isomitted in the substrate processing apparatus 1 b of FIG. 20. Thehydrophilic treatment is only performed on an outer annular surface 451b of the outermost cup part 45 (the outer annular surface 451 b includesa portion corresponding to the outer annular surface of the innercylindrical part 4511 in the outermost cup part 45 of FIG. 13). An innerannular surface 451 a of the outermost cup part 45 and inner annularsurfaces 421 a, 431 a, 441 a and outer annular surfaces 421 b, 431 b,441 b of the other cup parts 42 to 44 are surfaces of electricalinsulation material and they have water repellency. An auxiliary drainpart 454, which spreads on an outside in a ring shape, is provided on alower end portion of the outermost cup part 45 and a top end of theauxiliary drain part 454 bends upwards. The auxiliary drain part 454formed of conductive material is grounded at a position away from theoutermost cup part 45 by a ground part 61. The shapes of the inner cupparts 42 to 44 and the other constituent elements of the substrateprocessing apparatus 1 b are the same as those in the substrateprocessing apparatus 1 a of FIG. 13.

A basic operation of the substrate processing apparatus 1 b is the sameas in the substrate processing apparatus 1 a of FIG. 13, but theoperation for preparation which is performed with use of the dummysubstrate is different from that in the substrate processing apparatus 1a. Specifically, in the operation using the dummy substrate (FIG. 2:Step S10), the elevating mechanism 5 moves the cup parts 42 to 45relatively to the substrate holding part 2 in a direction along thecentral axis J1 as a unit and an upper end portion of the annularsidewall 451 in the outermost cup part 45 is positioned below the dummysubstrate. Ejection of pure water is started (see FIG. 17) to form awater layer (shown by a thick line 75 b in FIG. 20) on the outer annularsurface 451 b of the outermost cup part 45 by the pure water splashedfrom the rotating dummy substrate, and then the operation for holdingliquid in the cup part with use of the dummy substrate is completed.Subsequently, the above Steps S11 to S16 in accordance with the basicoperation are performed on a substrate 9 to be actually processed,similarly to the substrate processing apparatus 1 a of FIG. 13.

Though frictional charging occurs in the inner annular surface 421 a ofthe cup part 42 due to the pure water splashed from the rotatingsubstrate 9 in Steps S12, S132 and S134, charged potential of the innercup part 42 can be suppressed to some extent by the water layer 75 bwith conductivity which is formed on the whole outer annular surface 451b of the outermost cup part 45, and therefore, it is possible to preventelectric discharge from occurring on the substrate 9.

As described above, the liquid including water is only held on the outerannular surface of the cup part in the substrate processing apparatuses1, 1 b of FIGS. 1, 4, and 20, the liquid including water is only held onthe inner annular surface of the cup part in the substrate processingapparatus 1 of FIG. 5, and the liquids including water are held on theinner annular surface and the outer annular surface of the cup part inthe substrate processing apparatus 1 a of FIG. 13. With this structure,it is possible to suppress charged potential of the cup part which ischarged by splashing of pure water. Accordingly, from the viewpoint ofsuppressing charged potential of the cup part, it is required that theliquid including water (i.e., water or liquid containing water) is heldon at least one surface of the inner annular surface and the outerannular surface of the cup part.

Depending on design of the substrate processing apparatus or a kind ofsolution used in the substrate processing apparatus, there is a casewhere, from the viewpoint of producing no effect on the process, it ispreferable the water layer 71 or 75 b is formed on the outer annularsurface 411 b of one cup part 41 or the outer annular surface 451 b ofthe outermost cup part 45 out of the plurality of concentric cup parts42 to 45, that is to say, the water layer 71 or 75 b is only formed on asurface on which the solution splashed from the substrate 9 does notadhere in substrate processing using the solution, like in the substrateprocessing apparatus 1 of FIG. 1 and the substrate processing apparatus1 b of FIG. 20. Therefore, in order to easily suppress charged potentialof the cup parts 41 to 45 without affecting the process, it ispreferable the liquid including water is held on the outer annularsurfaces 411 b, 451 b of the outermost cup parts 41, 45 which arelocated on the outermost side of at least one cup part.

FIG. 21 is a view showing another example of the substrate processingapparatus 1 b. The substrate processing apparatus 1 b of FIG. 21 isdifferent from the substrate processing apparatus 1 a of FIG. 18 in thatonly the outer annular surface 451 b of the annular sidewall 451 in theoutermost cup part 45A out of the cup parts 42A to 45A in FIG. 18 is thesurface of the conductive resin film 47, and the inner annular surface451 a of the outermost cup part 45 and the inner annular surfaces 421 a,431 a, 441 a and the outer annular surfaces 421 b, 431 b, 441 b of othercup parts 42A to 44A are surfaces of electrical insulation material andthey have water repellency. Also in the substrate processing apparatus 1b of FIG. 21, though frictional charging due to the pure water splashedfrom the substrate 9 occurs in the inner annular surface 421 a of thecup part 42A where the whole annular sidewall 421 is formed ofelectrical insulation material, charged potential of the inner cup part42A can be suppressed by the outermost cup part 45A to some extent andconsequently, it is possible to prevent occurrence of electric dischargeon the substrate 9.

Although only the outer annular surface of the cup part (the outermostcup part) includes the surface of the member with a resistivity which issmaller than that of the main body of the cup part in the substrateprocessing apparatuses 1, 1 b of FIGS. 6 and 21 and the inner annularsurface and the outer annular surface of the cup part include thesurfaces of the members with a resistivity which is smaller than that ofthe main body of the cup part in the substrate processing apparatus 1 aof FIG. 18, it is also possible to suppress charged potential of the cuppart by only including the surface of the member with a resistivitywhich is smaller than that of the main body, in the inner annularsurface of the cup part in the substrate processing apparatus. That isto say, in order to suppressing charged potential of the cup part whichis charged by splashing of pure water, it is required that at least onesurface of the inner annular surface and the outer annular surface ofthe cup part includes the surface of the member with a resistivity whichis smaller than that of the main body of the cup part.

FIG. 22 is a view showing still another example of the substrateprocessing apparatus 1 b. The substrate processing apparatus 1 b of FIG.22 is different from the substrate processing apparatus 1 a of FIG. 19in that the plurality of rod conductive members 47 c (shown by a thickline in FIG. 22) are only provided within the outermost cup part 45B,and the other constituent elements are the same as those in thesubstrate processing apparatus 1 a of FIG. 19. In the substrateprocessing apparatus 1 b of FIG. 22, charged potential of the inner cuppart 42B, which is generated by the pure water splashed from thesubstrate 9, can be suppressed by the outermost cup part 45B to someextent and consequently, it is possible to suppress occurrence ofelectric discharge on the substrate 9.

FIG. 23 is a view showing still another example of the substrateprocessing apparatus 1 b. Similarly to the substrate processingapparatus 1 of FIG. 12, the approximately cylindrical member 81 a isprovided around an annular sidewall 451 of the outermost cup part 45C inthe substrate processing apparatus 1 b of FIG. 23. The inner surface ofthe cylindrical member 81 a is along an outer annular surface 451 b ofthe annular sidewall 451 and a clearance is formed between the innersurface of the cylindrical member 81 a and the outer annular surface 451b. The cylindrical member 81 a is connected to a ground part 61 to begrounded. Also in the substrate processing apparatus 1 b having aplurality of cup parts 42C to 45C, since the conductive cylindricalmember 81 a is provided close to the outer annular surface 451 b of theoutermost cup part 45C similarly to the substrate processing apparatus 1of FIG. 12, charged potential of the inner cup part 42C which isgenerated by the pure water splashed from the substrate 9 can besuppressed to some extent and it is therefore possible to suppressoccurrence of electric discharge on the substrate 9.

As discussed above, since the cylindrical member with a resistivitywhich is smaller than that of the outermost cup parts 41C, 45C isprovided close to the outer annular surfaces 411 b, 451 b of theoutermost cup parts 41C, 45C which are located on the outermost side outof at least one cup part, it is possible to suppress charged potentialof the cup part without changing the structure of the cup part.

Though the substrate processing apparatuses 1, la, 1 b in accordancewith the first to third preferred embodiments have been discussed above,the substrate processing apparatuses 1, 1 a, 1 b allow variousvariations.

As described above, since the liquid including water (i.e., water orliquid containing water) is held on at least one surface of the innerannular surface and the outer annular surface of the cup part or atleast one surface of the inner annular surface and the outer annularsurface of the cup part includes the surface of the member with aresistivity which is smaller than that of the main body of the cup part,it is possible to suppress charged potential of the cup part in thesubstrate processing apparatus. In a case where an inner annular surfacewith water repellency is required for ensuring a constant drainingperformance, it is preferable the liquid including water is only held onthe outer annular surface or the surface of the member with aresistivity which is smaller than that of the main body is only includedin the outer annular surface, like the cup part 41 of FIG. 1, the cuppart 41 of FIG. 4, the cup part 41A of FIG. 6, the outermost cup part 45of FIG. 20, and the outermost cup part 45A of FIG. 21. On the otherhand, since frictional charging due to the pure water splashed from thesubstrate 9 normally occurs in the inner annular surface of the cuppart, the liquid including water is held on at least inner annularsurface or the surface of the member with the small resistivity isincluded in at least inner annular surface and thus, it is possible todecrease an amount of charge in the cup part and further suppresscharged potential of the cup part.

Though the liquid layer including water is formed on the inner annularsurface or the outer annular surface of the cup part by the processingliquid ejected from the processing liquid applying parts 3, 3 a in thesubstrate processing apparatuses 1, 1 a, 1 b of FIGS. 1, 4, 5, 13 and20, there may be a case like a cup part 41 shown in FIG. 24 where, forexample, a ring-shape supply pipe 481 is provided around an upper endportion of an annular sidewall 411 as a liquid supplying part and liquidincluding water with conductivity is supplied to an outer annularsurface 411 b of the annular sidewall 411 from a plurality of holes 482which are formed in the supply pipe 481. In the cup part 41 of FIG. 24,an approximately cylindrical auxiliary member 483 (Hatching of its crosssection is omitted in FIG. 24) is provided around the annular sidewall411. The inner surface of the auxiliary member 483 is along the outerannular surface 411 b and a small clearance is formed between the innersurface of the auxiliary member 483 and the outer annular surface 411 b.The liquid supplied from the supply pipe 481 can be held between theouter annular surface 411 b of the annular sidewall 411 and theauxiliary member 483. Also, in a case where the liquid supplying partfor continuously supplying liquid is provided like the cup part 41 inFIG. 24, for example, pure water or the like may be substantially heldon the outer annular surface of the cup part only by forming a pluralityof grooves in the outer annular surface, to form a surface layerbecoming conductive.

The technique of using the textile material 46 or the mesh member in thecup part 41 of FIG. 4 can be applied to the substrate processingapparatuses 1 a or 1 b of FIG. 13 or 20 having the plurality of cupparts 42 to 45.

As discussed above, since it is required to prevent metal impuritiesfrom adhering on the substrate 9 in the processing of the substrate 9 inthe substrate processing apparatus, metal cannot be normally used in theinternal portion of the cup part or the surface of the cup part.However, depending on design of the cup part, a kind of a substrate tobe processed or the like, there may be a case where a ring-shaped memberformed of metal which is hard to dissolve (such as gold or platinum) isprovided within the ring-shaped groove 415 instead of the sealed liquid47 b of FIG. 9 or the conductive member 47 c of FIGS. 11, 19 and 22 maybe formed of the metal. In order to surely prevent elution of metal inthe cup part, it is preferable the conductive member is formed ofnonmetal material.

The four conductive members 47 a are arranged in the circumferentialdirection of the annular sidewall 411 at regular intervals in the cuppart 41A of FIG. 8. From the viewpoint of suppressing charged potentialin the nearly whole circumference of the cup part 41A, however, it isimportant that a member, which has surface(s) included in the innerannular surface 411 a or the outer annular surface 411 b of the annularsidewall 411 and has a resistivity which is smaller than that of themain body of the cup part 41A, is provided as a set of three or moreelements (element members) which are arranged in the circumferentialdirection of the cup part 41A at regular intervals. Also in the cup part41B of FIG. 11, the four conductive members 47 c are arranged in thecircumferential direction of the annular sidewall 411 at regularintervals. In order to suppress charged potential in the nearly wholecircumference of the cup part 41B, it is important that an internalportion, which is provided in the annular sidewall 411 and has aresistivity which is smaller than that of the main body of the cup part41B, is provided as a set of three or more elements (element portions)which are arranged in the circumferential direction of the annularsidewall 411 at regular intervals.

Although pure water and the solution are applied onto the substrate 9from the processing liquid applying parts 3, 3 a in the above first tothird preferred embodiments, even in an apparatus for only applying purewater, electric discharge can occur on a substrate in a state wherewater remains on the substrate as discussed above. Therefore, it isimportant the above technique where charged potential of the cup part issuppressed to prevent occurrence of electric discharge on the substrateis used in a case where a substrate processing apparatus has aprocessing liquid applying part for applying at least pure water, ontothe substrate.

In the substrate processing apparatuses 1, la, 1 b of FIGS. 1, 4, 13 and20, the substrate 9 is held so that the normal direction of thesubstrate 9 is the vertical direction, the substrate 9 is cleaned bypure water in a state where the upper end portion of the cup part ispositioned below the substrate 9, and then the pure water is efficientlyapplied to the outer annular surface of the outermost cup part (in acase where only one cup part is provided, the outer annular surface ofthe cup part) in the course of processing of the substrate 9, therebyeasily forming the water layer. Conversely, when it is not required toapply pure water to the outer annular surface of the outermost cup part,the normal direction of the substrate 9 is not necessarily along thevertical direction. Also, application of pure water to the outer annularsurface of the outermost cup part does not necessarily have to beperformed in processing of all substrates 9 but may be only performed inprocessing of every predetermined number of substrates 9.

Although the processing liquid splashed from the substrate 9, which isrotated by the substrate holding part 2, is received by the cup part inthe substrate processing apparatuses 1, 1 a, 1 b, there may be a casewhere, for example, the rotation mechanism is omitted in the substrateholding part, pure water is applied onto the substrate 9 held by thesubstrate holding part, and thereafter the pure water which is splashedfrom the substrate 9 by air from an air knife provided separately isreceived by the cup part. Also in this case, the above technique ofsuppressing charged potential of the cup part should be used because thecup part is charged by the splashed pure water.

Thought the cup part moves up and down by the elevating mechanism 5 inthe above first to third preferred embodiments, the cup part is fixedand the substrate holding part 2 for holding the substrate 9 may bemoved up and down. In other words, the cup part moves up and downrelatively to the substrate holding part 2.

(The main bodies of) the cup parts in FIGS. 6 to 12, 18, 19, and 21 to23 are not necessarily formed of electrical insulation material. Themain body of the cup part where at least one surface of the innerannular surface and the outer annular surface includes the surface ofthe member with a resistivity which is smaller than that of the mainbody and the main body of the cup part where the internal portion has aresistivity which is smaller than that of the main body, may be formedof semiconductor material with a resistivity (for example, a resistivityof 2 M.OMEGA.cm or more) which is higher than that of the member or thatof the internal portion. Also in this case, charged potential of the cuppart can be suppressed by the member or the internal portion to reduceinduction charging of the substrate 9. Similarly, one cup part or theplurality of cup parts, where the cylindrical member is provided closeto the outer annular surface of the outermost cup part, may be formed ofsemiconductor material with a resistivity which is higher than that ofthe cylindrical member.

An object to be processed in the substrate processing apparatus may be asubstrate such as a glass substrate, other than a semiconductorsubstrate.

FIG. 25 is a view showing a construction of a substrate processingapparatus 1 c in accordance with the fourth preferred embodiment of thepresent invention.

The substrate processing apparatus 1 c shown in FIG. 25 has the sameconstruction as the substrate processing apparatus 1 of FIG. 1 exceptfor a cup part 141. In FIG. 25, a part of the substrate holding part 2is shown cross-sectionally for convenience of illustration (the same asin FIGS. 29 and 31 discussed later).

The cup part 141 has an annular sidewall 1411 which is arranged aroundthe chuck 21 to prevent processing liquid applied onto the substrate 9from being splashed around the annular sidewall 1411, and an upperportion of the annular sidewall 1411 is an inclined part 1412 whosediameter decreases toward the processing liquid applying part 3 (i.e.,upwards). A ring-shaped bottom part 1413, which protrudes toward thecentral axis J1 and covers the lower space of the chuck 21, is attachedto a lower end portion of the annular sidewall 1411, and a drain outlet(not shown) for draining the processing liquid is provided in the bottompart 1413.

FIG. 26 is a cross-sectional view of the cup part 141 at the positionindicated by the arrows in FIG. 25. As shown in FIGS. 25 and 26, anannular sidewall 1411 of the cup part 141 has a deep ring-shaped groove1415 around the central axis J1 and the ring-shaped groove 1415 isfilled with a pure water 147. As shown in FIG. 25, since an opening ofthe ring-shaped groove 1415 which is on the side of an inclined part1412 is closed by a ring-shaped lid member 1416, the pure water 147 isheld (sealed) in the annular sidewall 1411. The main body of the cuppart 141 is formed of Teflon™ (in the cup part 141 of FIG. 25, the mainbody is a part excluding a portion of the pure water 147 in the annularsidewall 1411) and an inner annular surface 1411 a has water repellency(hydrophobicity). A relative dielectric constant (relative permittivity)of the pure water 147 held in the annular sidewall 1411 is about 80which is higher than that of Teflon™ forming the main body of the cuppart 141 (the relative dielectric constant of Teflon™ is about 3 to 4).

Next discussion will be made on an operation flow of the substrateprocessing apparatus 1 c for processing a substrate by applying theprocessing liquid onto the substrate with reference to FIG. 27. First,the cup part 141 is moved down by the elevating mechanism 5 to positionan upper end portion of the cup part 141 below the chuck 21, a substrateto be processed is placed on the chuck 21 by an external carryingmechanism, and held by the substrate holding part 2 (i.e., the substrate9 is loaded). The cup part 141 is moved upwards to dispose the chuck 21in the cup part 141 and the substrate 9 is surrounded by the cup part141 (Step S111).

Rotation of the substrate 9 is started by the substrate holding part 2,pure water is applied on onto the upper surface of the substrate 9 byopening the pure water valve 331 in the processing liquid applying part3, and thereby pre-rinse using pure water is performed on the substrate9 (Step S112). In this time, the pure water which is applied from theprocessing liquid applying part 3 and is splashed from the rotatingsubstrate 9 is received by the inner annular surface 1411 a of the cuppart 141, to cause frictional charging in the inner annular surface 1411a of the cup part 141. In the substrate processing apparatus 1 c,however, since a charge capacity (capacitance) of the annular sidewall1411 becomes large by holding the pure water 147 with a dielectricconstant, which is higher than that of the main body, in the annularsidewall 1411, a charged potential (relative to a ground potential) ofthe inner annular surface 1411 a is not greatly increased relatively toan electric charge generated in the inner annular surface 1411 a (i.e.,charged potential of the cup part 141 is suppressed in comparison with acase where the pure water 147 is not held or the ring-shaped groove 1415is not formed in the annular sidewall 1411). Therefore, the substrate 9placed on the chuck 21 is hardly charged by induction.

Next, the pure water valve 331 is closed in the processing liquidapplying part 3 and the processing liquid applied onto the upper surfaceof the substrate 9 is switched from the pure water to the solution byopening the solution valve 332 (Step S113). Application of the solutiononto the substrate 9 is continued for a predetermined time period toperform a processing using the solution on the substrate 9. Similarly tothe case of application of pure water, the solution which is appliedfrom the processing liquid applying part 3 and is splashed from therotating substrate 9 is received by the inner annular surface 1411 a ofthe cup part 141 and drained from the drain outlet in the bottom part1413.

After the solution is applied onto the substrate 9 for the predeterminedtime period, the solution valve 332 is closed and the pure water valve331 is opened. Thus, the processing liquid applied onto the uppersurface of the substrate 9 is switched from the solution to the purewater, and thereby post-rinse using pure water is performed on thesubstrate 9 (Step S114).

After completion of the post-rinse for the substrate 9 using the purewater, ejection of pure water is stopped and rotation of the substrate 9is stopped. The upper end portion of the cup part 141 (an end portion ofthe inclined part 1412) moves below the chuck 21 by the elevatingmechanism 5, the substrate 9 is taken out by the external carryingmechanism (i.e., the substrate 9 is unloaded) (Step S115), and then thenext substrate 9 to be processed is placed on the chuck 21 and disposedin the cup part 141 (Steps S116, S111). Then, the pre-rinse of thesubstrate 9 using the pure water (Step S112), the processing of thesubstrate 9 using the solution (Step S113), and the post-rinse of thesubstrate 9 using the pure water (Step S114) are performed similarly tothe above operation. After completion of the post-rinse for thesubstrate 9, the substrate 9 is unloaded (Step S115).

After the processes in the above Steps S111 to S115 are repeated foreach of a desired number of the substrates 9 (Step S116), operations inthe substrate processing apparatus 1 c are completed.

As discussed above, the annular sidewall 1411, which receives theprocessing liquid splashed from the substrate 9 by surrounding thesubstrate holding part 2, has the pure water 147 as an internal portionof the annular sidewall 1411, the internal portion (pure water 147) hasa dielectric constant which is higher than that of the electricalinsulation material forming the main body of the cup part 141 andextends continuously in a circumferential direction of the annularsidewall 1411 in the substrate processing apparatus 1 c in FIG. 25. Withthis structure, it is possible to suppress the charged potential of thecup part 141 generated in splashing of the pure water, in the wholecircumference of the annular sidewall 1411, without greatly increasingthe manufacturing cost of the substrate processing apparatus 1 c byforming the whole cup part with special conductive material. As aresult, it is possible to prevent electric discharge from occurring onthe substrate 9 due to induction charging of the substrate 9, inapplication of the processing liquid onto the substrate 9. Though thereis a possibility that charging of the substrate causes adhesion ofunwanted particles, which exist in atmosphere, on the substrate, sincecharging of the substrate is suppressed in the substrate processingapparatus 1 c, it is possible to prevent adhesion of such particles.

In the meantime, it is required to prevent metal impurities fromadhering on the substrate 9, for maintaining a constant yield inmanufacturing of semiconductor products, in processing of the substrate9 in the substrate processing apparatus 1 c. However, since only purewater is held in the annular sidewall 1411 and metal is not used in thecup part 141 of FIG. 26, there is no possibility that the above problemof metal contamination occurs (the same as in cup parts in FIGS. 28 to31 discussed later).

FIG. 28 is a view showing another example of the cup part and is across-sectional view of a cup part 141 a corresponding to FIG. 26. Inthe cup part 141 a of FIG. 28, a plurality of deep holes 1415 a in eachof which a cross section perpendicular to the central axis J1 is roundshape (actually, four holes 1415 a each of which has an approximatelysame depth as the ring-shaped groove 1415 of FIG. 25) are formed, theyare arranged in a circumferential direction of the annular sidewall 1411at regular intervals (that is to say, the plurality of deep holes 1415 aare arranged along a circle around the central axis J1 at equal angleintervals), and a cylindrical member 147 a is inserted into each hole1415 a. The cylindrical member 147 a is formed of ceramic such assilicon carbide (SiC) with a dielectric constant which is higher thanthat of the main body of the cup part 141 formed of electricalinsulation material (a relative dielectric constant of SiC is 10). Asdiscussed above, in the case that the cup part 141 a has an internalportion which is a set of cylindrical members 147 a arranged in thecircumferential direction of the annular sidewall 1411 as parts of theannular sidewall 1411 and the internal portion has a dielectric constantwhich is higher than that of the electrical insulation material formingthe main body of the annular sidewall 1411, it is possible to suppressthe charged potential of the cup part 141 a due to the splashed purewater in the substrate processing apparatus 1 c. The cup part 141 a ofFIG. 28 can be easily produced at low cost only by providing the holes1415 a in the annular sidewall 1411 formed of electrical insulationmaterial and inserting the cylindrical members 147 a into the holes 1415a, without greatly increasing the manufacturing cost of the substrateprocessing apparatus 1 c.

FIG. 29 is a view showing another example of the substrate processingapparatus 1 c and FIG. 30 is a cross-sectional view of a cup part 141 bat the position indicated by the arrows IV-IV in FIG. 29. In the annularsidewall 1411 of the cup part 141 b shown in FIGS. 29 and 30, aplurality of recessed portions 1415 b each extending along the centralaxis J1 are formed on an outer annular surface 1411 b, they are arrangedin a circumferential direction of the cup part 141 b at regularintervals, and a plate member 147 b is fitted into each recessed portion1415 b. Actually, the thickness of the plate member 147 b is madeapproximately the same as the depth of the recessed portion 1415 b (thedepth in a direction perpendicular to the central axis J1), and surfacesof the plate members 147 b, which are opposite to the other surfacesfacing the central axis J1, are included in the outer annular surface1411 b of the annular sidewall 1411. The plate member 147 b is formed ofceramic with a dielectric constant which is higher than that of the mainbody of the cup part 141 b formed of electrical insulation material (inthe cup part 141 b of FIG. 29, the main body is a part excluding theplate members 147 b in the annular sidewall 1411).

As described above, in the case that the surface of the annular sidewall1411 has the plate members 147 b with a dielectric constant which ishigher than that of the main body of the cup part 141 b, the chargecapacity of the annular sidewall 1411 becomes large, thereby suppressingthe charged potential of the cup part 141 b generated in splashing ofthe pure water. The cup part 141 b of FIG. 29 can be easily produced atlow cost only by providing the recessed portions 1415 b in the annularsidewall 1411 formed of electrical insulation material and fitting theplate members 147 b into the recessed portions 1415 b. Depending ondesign of the substrate processing apparatus 1 c, a member formed ofceramic may be provided on the outer annular surface 1411 b of theannular sidewall 1411 in a ring shape.

In the cup parts 141, 141 a, 141 b of FIGS. 26, 28, and 30, the annularsidewall 1411 has the pure water 147, (a set of) the cylindrical members147 a, or (a set of) the plate members 147 b, with a dielectric constantwhich is higher than that of the insulating main body, as an auxiliarydielectric material for increasing a charge capacity of the cup part141, 141 a, or 141 b. The auxiliary dielectric material is provided asthe internal portion of the annular sidewall 1411 or is provided on thesurface of the annular sidewall 1411. As a result, it is possible tosuppress the charged potential of the cup parts 141, 141 a, 141 bgenerated in splashing of the pure water, however, the above techniquecan be applied to a substrate processing apparatus having a plurality ofcup parts.

FIG. 31 is a view showing a part of a construction of a substrateprocessing apparatus 1 d having a plurality of cup parts 142 to 145 andonly shows a right side of a cross section of the plurality of cup parts142 to 145, the cross section being perpendicular to a substrate 9. Inthe substrate processing apparatus 1 d of FIG. 31, a plurality of kindsof solution and pure water can be ejected from a processing liquidapplying part 3 a, and the plurality of cup parts 142 to 145 move as aunit. A position of the plurality of cup parts 142 to 145 relative tothe substrate 9 is changed in accordance with a kind of processingliquid ejected from the processing liquid applying part 3 a. Forexample, the substrate 9 is disposed in a position below an inclinedpart 1422 of an inner annular sidewall 1421 in a case where pure wateris applied from the processing liquid applying part 3 a (the position isshown by solid lines in FIG. 31 and hereinafter, referred to as “purewater applying position”). The substrate 9 is disposed in a positionbetween the inclined part 1422 of the annular sidewall 1421 and aninclined part 1432 of an annular sidewall 1431 which is located outsidethe annular sidewall 1421, in a case where one type of solution isapplied (the position is shown by a double-dashed line in FIG. 31). Alsoin the inner cup part 142 shown in FIG. 31, the cylindrical member 147 ais provided in the annular sidewall 1421 similarly to the cup part 141 aof FIG. 28 (Actually, the plurality of cylindrical members 147 a arearranged in a circumferential direction of the annular sidewall 1421 atregular intervals). With this structure, it is possible to suppress thecharged potential of the cup part 142 generated in splashing of the purewater and prevent occurrence of electric discharge on the substrate 9.Similarly to the cup part 141 of FIG. 25, pure water may be held in theannular sidewall 1421 as the internal portion.

Herein, discussion will be made on an example of an electric dischargephenomenon which occurs on a substrate in a substrate processingapparatus in accordance with a comparative example. The substrateprocessing apparatus has the same construction as the substrateprocessing apparatus 1 d of FIG. 31 and the auxiliary dielectricmaterial is not provided in the inner cup part. In the substrateprocessing apparatus of comparative example, pure water is applied ontothe substrate in a state where the substrate is positioned in the purewater applying position, the pure water is splashed on the innermost cuppart, and then the cup part is charged after the pure water is drippedfrom the cup part. Then, the main body of the substrate is charged byinduction because of charging of the cup part. In this time, if the purewater remains on the substrate, CO₂ and the like normally dissolve intothe pure water on the substrate, the pure water changes to water withconductivity, and consequently, electric discharge can occur on thesubstrate. Also, if the cup parts move up and down in a state where thewater becoming conductive remains on the substrate, a relative positionbetween the substrate and the charged cup part is changed to alter thepotential of the main body of the substrate. As a result, electricdischarge can occur on the substrate (that is to say, dielectricbreakdown of an insulating film on the substrate occurs) when the cupparts move up and down.

On the other hand, in the substrate processing apparatus 1 d of FIG. 31,since the cylindrical member 147 a with a dielectric constant which ishigher than that of the main body is provided in the annular sidewall1421 of the cup part 142, it is possible to suppress the chargedpotential of the cup part caused by the splashed pure water. As aresult, it is possible to prevent electric discharge from occurring onthe substrate 9 due to charging of the cup part, in application of theprocessing solution onto the substrate 9, up and down movement of thecup parts 142 to 145, or the like. Also, it is possible to suppressadhesion of unwanted particles on the substrate which is caused bycharging of the substrate.

Though the substrate processing apparatuses 1 c, 1 d in accordance withthe fourth preferred embodiment have been discussed above, the substrateprocessing apparatuses 1, 1 b allow various variations.

In the cup part 141 of FIG. 26, liquid other than water with adielectric constant which is higher than that of the main body of thecup part 141 may be held in the annular sidewall 1411. However, sincepure water is normally used in processing of the substrate 9, in a casewhere pure water is held in the annular sidewall 1411, even if purewater leaks from the annular sidewall 1411, the substrate 9 held in thecup part 141 is not affected.

A ring-shaped member formed of ceramic may be inserted in thering-shaped groove 1415 in the cup part 141 of FIG. 26, and pure wateris sealed within the holes 1415 a in the cup part 141 a of FIG. 28. Itis possible to ensure constant strength without increasing thickness ofthe annular sidewall in a case where a member(s) of ceramic is providedin the cup part, and the material cost can be reduced in a case wherepure water is held in the cup part. Naturally, portions of ceramic andportions of pure water may formed in the annular sidewall so that theirpositions in the circumferential direction are shifted mutually.

Though the plate members 147 b can be provided in the inner annularsurface 1411 a of the cup part 141 b in FIG. 30, in this case, it isrequired the plate members 147 b have corrosion resistance against thesolution (in the case that the inner annular surface 1411 a of the cuppart 141 b has water repellency, the plate members 147 b additionallyhave water repellency), and therefore, there is a possibility thatsurface treatment to the plate members 147 b or the like must beperformed. Therefore, it is preferable the surfaces of the plate members147 b are made to parts of the outer annular surface 1411 b of theannular sidewall 1411 in order to easily providing the plate members 147b on the surface of the annular sidewall 1411.

In the cup parts 141 a, 141 b of FIGS. 28 and 30, the cylindricalmembers 147 a or the plate members 147 b are used as auxiliary elements.A set of four auxiliary elements, which are arranged in thecircumferential direction of the annular sidewall 1411 at regularintervals, functions as the auxiliary dielectric material for increasingthe charge capacity of the cup part, thereby suppressing the chargedpotential in each position of the cup part 141 a or 141 b. From theviewpoint of suppressing the charged potential in the nearly wholecircumference of the cup part, it is important the auxiliary dielectricmaterial is provided as a set of three or more auxiliary elementsarranged in the circumferential direction of the annular sidewall 1411at regular intervals.

The main body of the cup part is not necessarily formed of Teflon(trademark) but may be formed of electrical insulation material such asother fluorine resin or vinyl chloride resin. In the substrateprocessing apparatus, since the dielectric constant of the auxiliarydielectric material which is provided as the internal portion of theannular sidewall or is provided on the surface of the annular sidewall,is made higher than that of the electrical insulation material formingthe main body of the cup part, it is possible to suppress the chargedpotential of the cup part generated in splashing of the pure water.

Although pure water and the solution are applied onto the substrate 9from the processing liquid applying parts 3, 3 a in the fourth preferredembodiment, even in an apparatus for only applying pure water, electricdischarge can occur on a substrate in a state where water remains on thesubstrate as discussed above. Therefore, in a case where the substrateprocessing apparatus has a processing liquid applying part for applyingat least pure water onto the substrate, it is important an auxiliarydielectric material with a dielectric constant which is higher than thatof the main body of the cup part is provided as the internal portion ofthe annular sidewall or is provided on the surface of the annularsidewall to suppress the charged potential of the cup part.

Although the processing liquid splashed from the substrate 9, which isrotated by the substrate holding part 2, is received by the cup part inthe substrate processing apparatuses 1 c, 1 d, there may be a casewhere, for example, the rotation mechanism is omitted in the substrateholding part, pure water is applied onto the substrate 9 held by thesubstrate holding part, and thereafter the pure water which is splashedfrom the substrate 9 by air from an air knife provided separately isreceived by the cup part. Also in this case, the above technique ofsuppressing the charged potential of the cup part should be used becausethe cup part is charged by the splashed pure water.

An object to be processed in the substrate processing apparatus may be asubstrate such as a glass substrate, other than a semiconductorsubstrate.

While the invention has been shown and described in detail, theforegoing description is in all aspects illustrative and notrestrictive. It is therefore understood that numerous modifications andvariations can be devised without departing from the scope of theinvention.

This application claims priority benefit under 35 U.S.C. Section 119 ofJapanese Patent Application No. 2006-251637 filed in the Japan PatentOffice on Sep. 15, 2006, Japanese Patent Application No. 2006-327938filed in the Japan Patent Office on Dec. 5, 2006 and Japanese PatentApplication No. 2006-328648 filed in the Japan Patent Office on Dec. 5,2006, the entire disclosures of which are incorporated herein byreference.

What is claimed is:
 1. A substrate processing apparatus for processing asubstrate by applying processing liquid onto said substrate, comprising:a holding part including a chuck for holding a substrate; a processingliquid applying part including a supply pipe connected to a pure watervalve for applying pure water, which is one type of processing liquid,onto said substrate; a cup part which is formed of electrical insulationmaterial and surrounds said holding part to receive processing liquidsplashed from said substrate, said liquid including water and being heldon at least one surface of an inner annular surface and an outer annularsurface of said cup part; and a ground part having a conductive memberarranged in contact with and substantially electrically grounding saidliquid held on said at least one surface.
 2. The substrate processingapparatus according to claim 1, wherein hydrophilic treatment isperformed on said at least one surface of said cup part.
 3. Thesubstrate processing apparatus according to claim 1, wherein said cuppart has a textile member or a mesh member in said at least one surface.4. The substrate processing apparatus according to claim 1, wherein anormal direction of said substrate is a vertical direction and said cuppart moves up and down relatively to said holding part by an elevatingmechanism having a cylinder or motor arranged for moving the cup part upand down, said at least one surface includes said outer annular surface,and said elevating mechanism positions an upper end portion of said cuppart below said substrate while pure water is ejected from saidprocessing liquid applying part, to apply pure water splashed from saidsubstrate to said outer annular surface.
 5. The substrate processingapparatus according to claim 1, wherein said at least one surfaceincludes said inner annular surface.
 6. The substrate processingapparatus according to claim 1, wherein said at least one surface issaid outer annular surface and said inner annular surface has waterrepellency.
 7. The substrate processing apparatus according to claim 1,further comprising another cup part formed of the same material as saidcup part, at least one surface of an inner annular surface and an outerannular surface of said another cup part being formed in the same manneras said at least one surface of said inner annular surface and saidouter annular surface of said cup part, said another cup part beinglocated inside said cup part, a distance between said another cup partand said processing liquid applying part being longer than that betweensaid cup part and said processing liquid applying part, wherein said cuppart and said another cup part are movable relatively to said holdingpart in a normal direction of said substrate.
 8. The substrateprocessing apparatus according to claim 1, further comprising anothercup part formed of the same material as said cup part, an inner annularsurface and an outer annular surface of said another cup part beingsurfaces of said material, said another cup part being located insidesaid cup part, a distance between said another cup part and saidprocessing liquid applying part being longer than that between said cuppart and said processing liquid applying part, wherein said cup part andsaid another cup part are movable relatively to said holding part in anormal direction of said substrate.
 9. A substrate processing apparatusfor processing a substrate by applying processing liquid onto saidsubstrate, comprising: a holding part including a chuck for holding asubstrate; a processing liquid applying part including a supply pipeconnected to a pure water valve for applying pure water, which is onetype of processing liquid, onto said substrate; and at least one cuppart, wherein said at least one cup part is formed of electricalinsulation material and surrounds said holding part to receiveprocessing liquid splashed from said substrate, wherein liquid includingwater is held on an outer annular surface of an outermost cup part outof said at least one cup part.
 10. The substrate processing apparatusaccording to claim 9, further comprising a ground part having aconductive member arranged in contact with and substantiallyelectrically grounding said liquid held on said outer annular surface ofsaid outermost cup part.
 11. The substrate processing apparatusaccording to claim 9, wherein hydrophilic treatment is performed on saidouter annular surface of said outermost cup part.
 12. The substrateprocessing apparatus according to claim 9, wherein said outermost cuppart has a textile member or a mesh member in said outer annularsurface.
 13. The substrate processing apparatus according to claim 9,wherein a normal direction of said substrate is a vertical direction andsaid at least one cup part moves up and down relatively to said holdingpart by an elevating mechanism having a cylinder or motor arranged formoving the cup part up and down, and said elevating mechanism positionsan upper end portion of said at least one cup part below said substratewhile pure water is ejected from said processing liquid applying part,to apply pure water splashed from said substrate to said outer annularsurface.
 14. A substrate processing apparatus for processing a substrateby applying processing liquid onto said substrate, comprising: a holdingpart including a chuck for holding a substrate; a processing liquidapplying part including a supply pipe connected to a pure water valvefor applying pure water, which is one type of processing liquid, ontosaid substrate; and a cup part whose main body is formed of electricalinsulation material, said cup part having an annular sidewallsurrounding said holding part to receive processing liquid splashed fromsaid substrate, an auxiliary dielectric material with a dielectricconstant, which is higher than that of said electrical insulationmaterial, being provided as an internal portion of said annular sidewallor being provided on a surface of said annular sidewall.
 15. Thesubstrate processing apparatus according to claim 14, wherein saidauxiliary dielectric material extends continuously in a circumferentialdirection of said annular sidewall.
 16. The substrate processingapparatus according to claim 14, wherein said auxiliary dielectricmaterial is a set of three or more auxiliary elements which are arrangedin a circumferential direction of said annular sidewall at regularintervals.
 17. The substrate processing apparatus according to claim 14,wherein said auxiliary dielectric material is ceramic.
 18. The substrateprocessing apparatus according to claim 14, wherein said auxiliarydielectric material is liquid held in said annular sidewall.
 19. Thesubstrate processing apparatus according to claim 14, wherein saidauxiliary dielectric material is a member which is provided as a part ofan outer annular surface of said annular sidewall.